1. Field of the Invention
The present invention relates to a control apparatus and method for controlling a projector apparatus.
2. Description of the Related Art
Recently, the tendency of networks such as the Internet to feature high bandwidth is increasing and video conference systems have become widely used that are capable of communicating not only audio signals but video signals as well. In video conferencing systems, there are cases wherein it is desirable for a plurality of images to be projected on the same screen at one location. For example, there are cases when it is desirable to simultaneously project the meeting room of the other party while material commonly used in video conference systems is being projected. Further, in addition to that, there are cases wherein it is also desirable to simultaneously project an image of the local meeting room. Thus, as a simple method to project a plurality of images on the same screen, there is a method to project using a separate projector apparatus for each image. In this case, it is considered necessary to bring portable projector apparatuses in to the meeting room when the number of locations connected to the video conferencing system is increased.
Users of the video conferencing system are required to adjust the projection positions or projection sizes of the image that the respective projector apparatuses project before the videoconference can start. For example, a user may make adjustments so that the projection positions do not overlap, or may adjust the projection size such that the size of the human image projected on the screen is comparable to that of a person actually in the local meeting room.
In connection with such video conferencing system, the following technology is proposed.
Projector Communication Technology
A projector apparatus having a communicating function is released. In Japanese Patent Laid-Open No. 2006-3903, technology is disclosed which synchronizes the contents displayed by centrally controlling a plurality of projector apparatuses which are capable of communicating via a personal computer. In Japanese Patent Laid-Open No. 2004-239968, technology is disclosed to manage the role of a plurality of projector apparatuses having a communication function. The described invention assumes a client-server relationship between the projector apparatuses in particular, whereby a client projector apparatus is capable of receiving an image from a server projector apparatus. In Japanese Patent Laid-Open No. 2006-246038, a method is described whereby the image for the video conferencing system is transferred to a projector apparatus having a communicating function. In particular, a display device can be selected dynamically, despite prior settings.
Projector Image Linking Technology
A video-wall display technology is provided whereby one image is projected on a screen from a plurality of images by linking the projected image of a plurality of projector apparatuses. Japanese Patent Laid-Open Nos. 2001-268476 and 2004-356919 describe judging the overlap or correction of projected images.
Network Camera Technology
In Japanese Patent Laid-Open No. 10-164420, a network camera is provided comprising an image capturing unit and a network unit, which distributes a captured image to the other party of the communication and receives a control signal for the camera from the other party of the communication.
Human Image Detecting Technology
For example, in “Face Detection for Multi-modal Speech Recognition” Kazumasa Murai, Satoshi Nakamura; (Information Processing Society of Japan, Journal of Spoken Language Information Processing Vol. 2002, No. 10, pp. 39-44; Feb. 1, 2002), technology is provided to detect a human area in an image. Further, face (or individual) recognition technology is also used to check the extracted feature amount of the face of the human image with an existing feature amount database for each individual.
Home Network Connection Technology
DLNA (Digital Living Network Alliance) assumes the presence of audio/video distribution in a home network and provides a specification relating to the interoperability of network apparatuses (DLNA-version 1.5 “DLNA Network Device Interoperability Guidelines expanded: March 2006” (Digital Living Network Alliance; March 2006)). DLNA v1.5 strictly specifies that the audio/video codec and transfer protocol are to be based on the UPnP specification (including UPnP AV specification) in order to realize an improvement of the interoperability of the network apparatuses. Detection of the network apparatuses is based on SSDP (Simple Service Discovery Protocol).
However, even if one of these technologies is used, it takes time to adjust the multi-screen display and to correct the image (i.e., to perform calibration of the size or position) when a plurality of projector apparatuses is used. In particular, because of an increased need to adjust or correct the image, the above problem becomes worse in situations where a portable projector apparatus is used.
The present invention provides a projector system that includes a plurality of projector apparatuses for projecting images on the same screen, whereby the adjustment of projection parameters for each projector apparatus can be achieved efficiently.